Brick press liner



v July 20, 1943.

G. E. 'sElL 2,324,884

BRICK PRESS LINER Filed March ll. 1942 2 Sheets-Sheet l 20, v vG1. E. SVEL BRICK PRESS LINER Filed March 11.l 1942 2 Sheets-Sheet 2 Patented July 20, 1943 BRICK PRESS LINER Gilbert E. Seil, Cynwyd, Pa, assigner toE. J. Lavino and Company, Philadelphia, Pa., a cor- 1 poration of Delaware Application March 11, 1942, serial No. 434,197

(o1. 2li-122)V 2 Claims.

This invention relates to Wall-forming members for molds or dies, especiallyv Such as are used in brick presses and similar equipment in which material is formed into desired shapes un der pressure. This invention has as an object the providing of wearand abrasion-resistant molding surfaces for such dies.

Brick presses are well known and are characterized in their pressing operation by two vertically acting opposed plungers that move into a mold bcx having sides and ends. These wallforming members of the mold box are subject to considerable wear, especially when bricks made of abrasive or refractory material are pressed into form. Steel liners for these sides and ends of a mold box have been tried. Even when made of special alloy steel that has been especially heat-treated and hardened, they are still subject to excessive wear and abrasion.v When worn, 'the liners form a mold which yields a shape larger than the one desired. In addition the shapes taken from a worn mold are frequently distorted. The worn liner plates may be resurfaced and reeused by compensating with spacers behind the liner plates for the metal lost in resurfacing, but the press output is lost while the liner plates are being removed from the press, ground or resurfaced, and then replaced in the press. The first cost of such liners ishigh but to this must be added further costs of lost production, regrinding, and of making press changes.

So for many years efforts have been made to perfect press .liners so that they will withstand the abrasion encountered in the pressing of refractory brick and the subsequent movement of the brick in removing it from the mold or mold box. Effort was made to make the liners of materials harder than the brick-making material,

but it seemed impossible to maintain the abrasive resistant materials in place in the liners.

A more specific object of this invention there- .fore is to provide liner surfaces that will be more resistant to wear than the steel liners used heretofore. This object is realized by the use of abrasion-resistant insets or inserts carried by specially shaped steel liners.

A further object is to devise liners or liner plates for holding the abrasionu or wear-resistant insets whereby the pressure exerted on the liner plates when the mold is pulled tight, is always pressure of steel against steel, and. never steel against insert, or insert against insert. Such an arrangement overcomes the danger cf cracking er breaking the inserts because of pressure on their ends or edges. ylShis Yobject is realthis invention;

`is associated with the hopper.

ized by having each insert backed and partly or entirely framed or encircled at its lateral edges by sections of steel liners,

With thisfand other objects in View, as will become apparent as the description proceeds, the'V invention resides in certain novel features of construction, combination and arrangement of parts which will be'hereinafter more fully described and claimed.

, In the accompanying drawings: Y

Figure 1 shows a side sectional elevationy of a brick press showing rone environment in which the invention may be used; f

Fig. 2 is a working face view of a side mold plate or liner constructed ,in accordance with Fig. 3 shows'a sectional View on line 37-3 of Fig. 2; y v

Fig. 4 is a working face view of an end mold, plate or liner embodying the teaching of this in' vention; y I

Fig. 5 shows a sectional View on line 5.--5 of Fis. 4;

Fig. V6 is av partial horizontal sectional View taken through a corner of `a mold box whose compositeV liners or plates are made in accordance with this invention; and v Fig. '7 is a partial perspectiveviewof adjacent end and side' liners for the mold box. y

Fig. 1 shows a portion of a brick press in which the inventionmay be used, such as described'in the partent to Flood, No. 987,124. In this figure a stationary frame is shown at 3l and in this kframe slide the .bars 32.V At the lcwer end the `side bars carry the lower cross-head 34, which is .rigidly secured to the side bars and yieldingly supports the saddle 53 on which .are mounted the lower plungers 39, which reciprocate vertical# ly in the mold bex 40, 4I indicates avhopper for the material to be molded or pressed, and 42 indicates the table top. The charging box 4l A pitman lever 43 extends from'the toggle shaft 31 to a crank 44 of a crank shaft 45 that issuitably driven.

The side bars 32 reciprocate vertically in the frame 3| and 4during aportion of the cycle of the pressing operation, the side bar is supported on spring 46, while at the other portionthereof, the bars are supported from the toggles 35 and35, through the medium of the xed roller 41 and liftingcam-like shoeA 48 that is carried by pitman 43. `The lower toggle 36 is secured Ato upper cross-head 33 by means of shaft 5l. The

yupper toggle 35 is secured to the side bars 32 secured to side bars 32, but yieldingly supports a saddle 53 on which is mounted the lower plunger 39. The side arms, toggles, pitman, cross-heads and plungers or dies constitute a pressing mechanism which is free to slide vertically and which would fall if not supported. Rotation of the crank 44 clockwise oscillates the pitman 43 which, through the medium of shaft 31, operates the toggles and their train of mechanism. During a portion of the operating cycle the pressing mechanism is supported by a xed roller acting on the suitably shaped face of a shoe secured to the under side of the pitman, and during the remaining portion of the cycle the pressing mechanism is supported by springs supported on blocks fastened to the press frame and engaging shoulders near the tops of the side arms. The flexing and straightening of the toggles by the action of the pitman causes the upper and lower plungers to move toward and away from each other in the mold, permitting filling of the mold from the hopper 4I by reciprocation of the charging box 4I' when the plungers are farthest apart and obtaining the maximum pressure on the material B in the mold when the plungers are closest together.

In the brick presses of the above type, the action of the toggles and the pitman is such that the pitman flexes the togglees at one end of its stroke and brings them into straight or vertical alignment at the other end of the stroke, thus applying the maximum pressure` to the material in the mold only once during each pressing cycle.

The improved liners or composite plates for forming the walls of the mold box 40 of a brick press are shown in Figs. 2 to 6, wherein side plates or liners are indicated at I2, and end plates or liners are indicated at II. They each have a main body portion of steel. End plate II has a cut-away portion or section in its operative or working face to provide flanges I3 and I4 at each end thereof, adapted to hold between them an abrasion-resistant inset or insert I5 whose outer or working face is flush with the exposed edges of the flanges I3 and I II, Side plates or liners I2 have end anges I8 and I9, similar to end plate anges I3 and I4, but also side flanges I6 and I1, so that these anges I6, I'I, I8 and I9 together encircle or bound a recess 20 in the working face of the side plates into which fits ush another abrasive inset or insert 2|. The inserts are held in place in the respective cutaway portions of the end plates and recesses of the side plates by cement or other suitable adhesive. These inserts are formed of extremely abrasionand wear-resistant materials. Among such materials are natural and fused magnesia, hardness six on Mohs scale; natural and fused alumina, hardness nine on Mohs scale; silicon or tungsten carbide, hardness 9.5 on Mohs scale; and other metal carbides, tungsten or other borides, nitrides and diamond borts, most of which have hardnesses above 9 on Mohs scale. The facings may be made in various ways, for instance, the starting materials may be fused, cast and polished to yield a plate of the desired dimensions, or the plate may be made by pressing grains of the desired starting materials with a suitable bond, and processing to obtain a plate of the desired dimensions. It should be mentioned that when the abrasive-resistant inserts are used, regular carbon steel liners can be substituted for the special steel liners as backing `for the inserts, thus further reducing the cost of the installation.

Each side and end plate or liner for the press mold box has its insert of less area than the total area of the liner, and so secured and arranged therein that the insert of one will never press against the insert of another. This is emphasized in Figs. 6 and 7, from which it can be seen that a small clearance 22 is provided between the free ends of the inserts I5 of the end plates and the face of the insert 2| of the side plates. 'I'his small space will remain unlled or become lled with small amounts of the material being pressed. In either case no ill effects will result and the danger of cracking or breaking the inserts by pressure on the ends or side edges, is eliminated.

Each side plate I2 is held in place in the mold box by means of a projecting section or rib 23 on the back thereof that fits into a corresponding groove (not shown) in the mold box, and each end plate Il is similarly held by means of a projecting section or rib 24 on the back thereof. The vertical edges of the end plates Il taper slightly toward each other as shown in Fig. 4, so that the bottom flange I4 is slightly less long than the top flange I3.

This invention is especially useful in a Chisholm Boyd and White brick press, Which is well known and widely used for the forming of refractory bodies. In this type of press refractory mixes are pressed into brick and other desired .shapes by opposing plungers which operate in a mold, as shown in Fig. 1. In the pressing operation the mixture is pressed in `the mold by vertically acting opposed plungers which are moving with respect to the sides and ends of the mold at the time or times of application of the maximum pressure. Although the sides and ends of the mold are slightly tapered, making the top opening of the mold larger in area than the bottom, the movement of the compressed mixture subjects the sides and ends of the mold to considerable wear.

The wear is greatly aggravated when non-plastic mixes, containing abrasive grains, are formed into shapes at high pressures. For example, chrome refractory mixes having little or no plasticity and Containing a large percentage of recrystalllzed chi-omite grains are pressed into brick at pressures of 4000 to 10,000 pounds per square inch. Recrystallized chromite grains, prepared as described in my United States Patent N0. 2,028,017, have a hardness of 8.5 on the Mchns scale and fracture with sharp cutting edges, so that the pressed brick, moving under pressure in the mold, quickly Wears the usual hard steel liners suflicently to require replacement. For example, a brick mixture containing recrystallized chromite, made into standard 9" x 4 1/2 x 3 brick in a press operating at a speed oi eight cycles per minute and pressing four brick per cycle at a pressure of 4500 pounds per square inch, will wear the mold liners to a depth of .032" in twelve hours, and necessitate the removal and replacement of the liner. Changing the mold liners causes the press te lose its productive func-- tions for a period varying from three to ve hours, for although the mere physical change of liners can be made in approximateiy forty minutes, it usually requires ,three additional. hours of trial, ruiming and adjustment to properly reset the mold liners, plunger, etc.. so that the press' will function properly. The press then has operated twelve hours and been idle four hours and has yielded only 75% of its possible production.

These disadvantages are overcome and avoided by the use of the composite liners that carry abrasive inserts as proposed by this invention.

It must be understood that the invention is not limited to the examples given, but is applicable to all presses in which material is formed into shapes under pressure in mold boxes, the choice of the insert 'material being governed by the hardness of the material being pressed.

I claim: v

1. Composite wall members for a mold box comprising vertically disposed pairs of side framing plates and of end framing plates having recesses in their operative surfaces, and inserts of Wear-and abrasion-resistant materials located in v the recesses of said framing plates, characterized by the pair of side framing plates each having a margin section circumjacent to its embraced insert and the pair `of end framing plates eachhaving margin sections embracing its insert at the top and at the bottom but leaving the vertical boundaries of the insert exposed,` with the framl ing plates when arranged as a mold box providing plate-to-plate Contact but ne insert-to-insert v ing iace not covered by the insert, one pair of said framing plates each having a margin section cireurnjacent to its embraced insert and the other pair of end framing plates each having margin sections embracing its insert at the top and at the bottom, but leaving the vertical boundaries of the insert exposed, With the framing plates when arranged as a mold box providing plate-tm plate contact but no insert-to-insert contact and no plate-to-insert contact between angularly adjacent abutting framing plates.

GILBERT E. SEIL. 

